1. Field of the Invention
The present invention relates to an assembly for precisely positioning an element, e.g. a workpiece to be machined or a tool used in a machining apparatus, with reference to a reference center or axis of the machining apparatus. More particularly, the invention relates to a manufacturing jig adapted to precisely position a workpiece with reference to a workpiece receiving means, said jig comprising a workpiece supporting member to which the workpiece is fixed and a receiving member on which said workpiece supporting member is releasably mounted.
The expression "precisely positioning" shall express, in its widest sense, that an element, e.g. a workpiece to be machined or a machining tool used for machining a workpiece, is fixed within a machining device in a well defined and exactly known position. Particularly, according to a first aspect of the invention, the element shall be exactly positioned with reference to two directions running perpendicularly to each other in a first plane, e.g. in the vertical plane, with other words, in the X- and Y-directions, as well as with reference to its angular orientation in said first plane. According to a second aspect of the invention, additionally, an exact position with regard to the height of the element shall also be achieved, i.e. along the Z-axis which runs perpendicular to said aforementioned first plane. Such positioning is not so difficult to realize, but nevertheless very important as well.